The main sizes of the tapered roller Tapered Roller Bearing china bearings conform to DIN ISO 355 and DIN 720. Dimensional and running tolerances match tolerance course PN acc. to DIN 620. These tolerance classes are standard and are perfect for most applications.
The bearings are separable. This implies the bearing parts could be fitted independently of every other. The bearings are supplied without seals. They can be lubricated with grease or essential oil from the side.
The rollers are processed to create pore-like micro indents in the top of steel (rolling contact surface and roller mind). This microstructure helps maintain an oil film that’s well suited for tapered roller bearing applications. Improved essential oil film retention considerably inhibits surface damage, reaching more than eight times higher toughness and equal or better seizure resistance in comparison to conventional products.
Better 
lubricant oil accumulation and retention (easier to form oil film) in the roller surface contributes to 10% lower friction in low speeds compared to conventional products.
Tapered roller bearings can accept huge radial and axial loads. Axial loads are absorbed in only one course. For axial counter support another bearing attached inverse is required. Suitable for medium speeds.
Higher efficiency transmission systems have emerged as key to enhancing gasoline economy, so NSK attempt to develop a great reliability bearing with the capacity of overcoming these hurdles.
To boost fuel economy, there’s been a shift to using less lubricant and/or cheaper viscosity lubricant in transmission systems. Subsequently, tapered roller bearings in transmissions are being subject to increasingly severe lubrication circumstances, increasing the risk of lubrication oil film depletion (lean lubrication conditions), surface destruction, and bearing seizure.